The present invention relates to a hand power tool, in particular a hammer drill or an impact hammer.
In a known hand power tool disclosed for example in the German patent document DE 28 20 128 A1 the tool holder is connected of one piece with a rotary sleeve which is supported rotatably on a guide pipe and can be rotated by means of a rotary drive. The guide pipe is arranged fixedly on the machine housing and receives a drive piston of a so-called impact mechanism which is reciprocatingly axially movable by a wobble drive, and an axially displaceable impact piston or anvil. Between the drive piston and the anvil, an air cushion is provided. When the impact mechanism is turned on, the drive piston strikes through the air cushion on the anvil, and it gives an impact energy directly to the tool which is clamped axially displaceably and non rotatably in the tool holder. If in addition the rotary drive is turned on, the tool holder is rotated and the tool is rotated through it.
A known exchangeable tool holder for a hand power tool, in particular for a drill hammer and/or impact hammer as disclosed in the German patent document DE 32 05 063 C2 is fixed to be displaceable to a limited degree and to be non rotatable, by a locking device directly on the drive spindle which performs a rotary and a stroke movement. For this purpose the tool holder has an end region which is fittable on the drive spindle and is in a rotary connection with the drive spindle through a spline profile. In this end region at least one radial opening is provided, in which a ball is arranged radially displaceably as a locking body. The ball engages in a circumferential longitudinal groove formed in the drive spindle and locks the tool holder with an axial clearance from pulling out in an axial direction. A displacement sleeve which serves for clamping the tool in the tool holder engages the ball and blocks its radial displacement. When the displacement sleeve is manually displaced by force toward the front end, the at least one ball is released and the tool holder can be pulled from the guide pipe by displaceably held displacement sleeve.
In a known hand power tool with a rotatable guide pipe supported in the machine housing and an exchangeable tool holder arranged on the guide pipe in its end region extending outwardly beyond the machine housing (hammer drill Type No. 0611 249 700), the end portion of the tool holder which engages the guide pipe has four radial openings which are spaced from one another by a rotary angle of 90°, and a ball representing a locking body is radially displaceably inserted in the corresponding radial opening and secured from falling out of the radial opening. In the locking position of the tool holder the balls are located in troughs which are offset by the same rotary angle in the guiding pipe. A rotatably movably held displacement sleeve engages the balls with a radially inwardly projecting ring web and thereby prevents any radial displacement of the ball. When the displacement sleeve is manually placed rearwardly by a rotary-/displacement movement in direction of the machine housing, the ring web releases the balls and the tool holder can be removed from the guide pipe with the displaceably held displacement sleeve.